2. "When people think of mental activity, they tend to think of it as an ethereal zapping of electricity that has no cost to the body. That's not true, the brain is a massive blood and oxygen sink. You need stimulus and recovery in mental work in the same way that you need stimulus and recovery for sports."

4. "Email eats so much time. First, because it's everyone else's agenda for your time, often including manufactured emergencies. Second, email allows you to fool yourself into thinking you're being productive."

Only check it a few times a day, he tells us, and use an organization app like Boomerang is streamline the process.

5. "If everyone is defining a problem or solving it one way and the results are subpar, this is the time to ask, What if I did the opposite? Don't follow a model that doesn't work. If the recipe sucks, it doesn't matter how good a cook you are."

Don't take it on faith that the "received wisdom" has any wisdom in it, Ferriss says, test and hone the process.

6. "My quota is two crappy pages per day. I keep it really low so I'm not so intimidated that I never get started."

Making goals ridiculously easy to reach defuses procrastination. Ferriss tells 99u that he'll start his writing session at just two pages — and then crank, crank, crank until he can write no longer, until 4 or 5 a.m.

7. "Massive elimination is the most important step and the most neglected step for entrepreneurs."

Ferriss holds to the 80-20 rule: You get 80% of your value from 20% of the things you do. Applied to your working life, that means taking an inventory of the activities, clients, and projects that are most fruitful — then discarding the rest.

8. "The most important commonality is that the people who really are the best at what they do are very experimental and meticulous about tracking their variables. It doesn't matter if they're working with athletes or space shuttles. The principles are the same."

The highest performers, he tells AskMen, all take an iterative approach to the way they work. The key to iteration? Reflecting on what did and didn't work.

9. "I've interviewed everyone from gold medalists to CEOs who make $100 million a year, and their one common characteristic is the ability to 'single-task' without interruption."

To make lasting changes to your daily routines, Ferriss recommends starting small. If you want to start running, just put your sneakers on every morning. If you want to start writing a book, just put in two crappy pages a day. Make it easy for yourself.